Creating an object

A class is a blueprint for objects. The process of creating objects from a class is called instantiation. An object can be instantiated with a new statement from a class or through reflection. It must be instantiated before it is used.

A class contains a constructor method that is invoked to create objects from the class. It always has the same name as the class. Dart defines two types of constructors: generative and factory constructors.

A generative constructor

A generative constructor consists of a constructor name, a constructor parameter list, either a redirect clause or an initializer list, and an optional body. Dart always calls the generative constructor first when the class is being instantiated, as shown in the following code:

class SomeClass {
  // Default constructor
  SomeClass();
}

main() {
  var some = new SomeClass();
}

If the constructor is not defined, Dart creates an implicit one for us as follows:

class AnyClass {
  // implicit constructor
}

main() {...

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Mastering DART

By : Akopkokhyants

Mastering DART

By: Akopkokhyants

Overview of this book

Creating an object

A generative constructor

Mastering DART

By : Akopkokhyants

Mastering DART

By: Akopkokhyants

Overview of this book

Creating an object

A generative constructor

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